checkin of updates to latest version of widget tree format, includes tiddler, slider and tabs macros
added update for triple double-quotes macro params
removed version info
Merge tag 'v5.0.15-beta' of https://github.com/Jermolene/TiddlyWiki5

Version number update for 5.0.15-beta
merge to latest tw5
Merge remote-tracking branch 'upstream/master'
Merge remote-tracking branch 'upstream/master'
Merge branch 'master' of https://github.com/Jermolene/TiddlyWiki5
Merge remote-tracking branch 'upstream/master'
Removed unneeded CSS classes

Part of #764
Rename "titlebar" class to "tc-titlebar"

Part of #764
Rename "title" class to "tc-title"

Part of #764
Rename "story-river" class to "tc-story-river"

Part of #764
Rename "sidebar-header" class to "tc-sidebar-header"

Part of #764
Merge remote-tracking branch 'upstream/master'
Rename "btn-invisible" class to "tc-btn-invisible"

Part of #764
Rename "btn-icon" class "tc-btn-icon"

Part of #764
Rename class "btn-big-green" to "tc-btn-big-green"

Part of #764
Rename "modal-*" classes to "tc-modal-*"

Part of #764
Rename "tw-password-wrapper" class to "tc-password-wrapper"

Part of #764